Automatic safety-brake for tread-powers.



PATENTED O'C'I"l 9, 1906.

` R. E. LING.

AUTOMATIC SAFETY BRAKE EUR TREAD POWERS.

APILIOATION FILED APB.. 17, 1906..

m lhHHrnH UNITED STATES PATENT OFFICE.

AUTOMATIC SAFETY-BRAKE FOR TREAD-POWERS.

Specification of Letters Patent.

Patented Oct. 9, 1906.

Application iled April 17l 1906. Serial No. 312.205.

useful Improvements in Automatic Safety- Brakes for Tread-Powers and I do declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

My invention relates to improvements in automatic safety-brakes for tread-powers used in o erating threshing-machines and other macfiinery.

The object of the invention is to provide a simple and practical brake device of this character which will instantly and automatically stop the Whole machine should the driving-belt break or fly off.

With the above and other objects in view the invention consists of certain novel features of construction, combination, and arrangement of parts hereinafter described and claimed.

In the accompanying drawings, Figure 1 is a side view of a portionL of the frame of a tread-power, showing the application of my improved automatic safety-brake thereto, the parts being shown in their normal position in full lines and in their operated or set position in dotted lines and Fig. 2 is a detail vertical sectional view taken on the plane indicated by the line 2 2 in Fig. 1.

Referring to the drawings by numerals, 1 denotes a ortion of the frame of a treadpower whic is adapted for use in operating threshing-machines and other machinery and which may be of any desired form and construction. This frame, as shown, consists of upper and lower horizontal beams connected by uprights upon which my improved brake mechanism is mounted. The main `shaft 2 of the tread-power rojects through a suitable bearing provided etween two of the converging uprights, and upon its outer end is secured a combined band and brake wheel 3, which is connected by a driving belt or band 4 to the usual belt wheel or pulley (not shown) of the threshing-machine or other machinery to be operated by the treadower. The tread-power is provided with t e usual hand-brake lever 5, which is ivoted at 6 upon the frame 1 and carries a brake-shoe 7 to engage the brake-surface of the wheel 3; but my improved automatic safety-brake mechanism comprises an additional brake-lever 8, which is pivoted at 9 upon the frame and also carries a brake-shoe 10 to engage the brake or friction surface of the wheel 3. The brake-lever 8 is actuated downwardly for the purpose of causing its shoe to frictionally engage the wheel by means of a coiled spring l1, which surrounds a rod or link 12 between a head upon its lower end and a right-angular bracket 13, secured upon one of the uprights of the frame 1. This rod or link slides through an opening in said bracket and has its upper end loosely or pivotally connected to the lever 8, as shown The lever 8 is held elevated or in its normal position, so that its shoe is outy of contact with the brake-wheel, by a -trip device which is actuated automatically when the belt 4 breaks or slides off of its pulley. This trip mechanism comprises a latch-lever 15, a bell-crank 16', and a trip-lever 17. The latter is pivoted at 18 in a bracket 1 9 upon one of the uprights of the frame 1 and is connected by pivot-links 20 21 to the free end of the lever 8 andone arm of the bell-crank 16', respectively, the ends of said links 2O 21 being pivotally connected to the same arm or end of the lever 17 at points unequally distant from its pivot. Said end of the lever 17 is formed with a tongue 22, which is adapted to engage a roller 23, provided in the forked end 24 of the latch-lever 15. The opposite end of the latter carries a roller 25, which rests and turns normally upon the upper stretch of the belt or band 4, as clearly shown in full lines in Fig. 1 of the drawings, so that the engagement of the roller 23 with the tongue or end 22 of the lever 17 will hold the parts in their full-line position in said figure and retain the brake-shoe 10 out of contact with the brakewheel 3 against the tension of its actuatingspring 11. It will be seen that whenever the belt 4 breaks or slips oif of its pulleys the end of the latch-lever 15, which carries the roller 25 and which is heavier than its forked end, will drop and causethe roller 23 to free the trip-lever 17, so that the coiled spring 11 will pull the parts to the dotted-line position shown in Fig. 1, and thus instantly `and automatically apply the brake-shoe 10 `to the wheel 3. The latch-lever 15 is pivoted in a bracket 26 upon the frame 1 and concentric with the bell-crank 16, the other arm of which is loosely connected to the hand-brake lever 5 by a link connection 27, which con- IOO IIO

sists yof upper and lower links 28 29, having a sliding connection with each other at 30, the upper link being pivoted to the bell-crank and the lower link to a loop or eye 32 upon the lever 5. A guide 33 is provided upon one of the uprights of the frame l for the upper link, as shown in Fig. 1. By thus connecting the bell-crank to the lever 5 it will be seen that the mechanism may be .automatically set by depressing the latter.

The construction, operation, and advantages of' the invention will be readily understood from the foregoing description, taken in connection with the accompanying drawings.

It will be seen that the safety-brake will be instantly and automatically applied should any accident happen when the machine is in motion and it is necessary toy quickly shut down the power. Vithout this device it reqpires some minutes to stop the machineby t -e use of the ordinary hand-brake 5.

Various changes in the-form, proportion, and the minor details of construction may be resorted to without departing from the principle4 or sacriiicing any of the advantages of the invention as defined by the appended claims.

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, is-

l. The combination with a tread-power having a frame, a driving and brake wheel and a belt passed around said wheel, of a brake-lever carrying a shoe to coact with the brake-surface of said wheel, means for operating said brake-lever to apply its shoe to said wheel, a trip-lever, a connection between the latter and said brake-lever, a latch-lever having one end supported upon said belt and its other end engaged with said trip-lever, a

bell-crank, a connection between said bellcrank and said trip-lever, a second brake-lever'having a shoe to coact with said brakewheel, and a connection between said bellcrank and said second brake-leven/substantially as described.

2. The combination with a tread-power having a frame, a driving and brake wheel and a belt passed around said wheel, of a brake-lever carrying a shoe to coact with the brake-suriaceof said wheel, a spring for actuating said brake-lever to apply its Shoe to said wheel, a bell-crank, a trip-lever, links connecting said trip-lever to said brake-lever and said bell-crank, a latch-lever a roller upon the overbalanced end of said latch-lever to engage said belt, a roller upon the opposite end of said latch-lever adapted to engage one end of said trip-lever, a second lever, and a loose link connection between said second lever and said bell-crank, substantially as described.

In testimony whereoi` I have hereunto set my hand in presence of two. subscribing witnesses.

ROBERT II. LING. Witnesses.:

F. C. SHARBAUGH, PHILIP- N. SnETTIG. 

